Abstract

The population of giant Canada geese (Brantacanadensismaxima) in eastern South Dakota has increased substantially since reintroduction efforts began in the 1960s. Breeding population estimates of Canada geese exceeded the population management objective of the South Dakota Game, Fish and Parks by the mid-1990s and has continued to increase at an estimated rate of 3 to 5% per year. Goose-related crop damage complaints have also increased. In 1996, a September hunting season (September 1 to 15) was implemented in 10 counties in eastern South Dakota and was expanded in 2000 to include most of eastern South Dakota. We initiated this study during 2000 to 2004 to estimate survival, harvest, and recovery rates of giant Canada geese. We captured and leg-banded Canada geese in 7 counties in eastern South Dakota during the summers of 2000 to 2003. Of the total leg-banded sample (n = 3,839), we recovered 648 bands during the same year that they were placed on geese (i.e., direct harvest rate), and we recovered 645 banded geese in later years (i.e., indirect recovery rate). Estimates of annual survival rate (95% CI) for adults and immatures were 0.52 (0.46 to 0.59) and 0.68 (0.57 to 0.79), respectively. Estimates of annual recovery rates (95% CI) for adult and immature geese were 0.16 (0.13 to 0.19) and 0.18 (0.14 to 0.21), respectively. Of the total recoveries, 77 and 69% of direct and indirect band recoveries, respectively, occurred in South Dakota. The composite harvest rate estimate during the period studied was 0.22 (0.20 to 0.24). Forty-nine percent of adult recoveries and 44% of immature recoveries (direct and indirect pooled for both age classes) occurred during the September season. In comparison to a previous band-recovery study of resident giant Canada geese in eastern South Dakota, survival rates for both adult and immature geese have declined, while recovery and harvest rates have increased. Survival estimates for this study were some of the lowest documented for giant Canada geese. However, it appears that even with a September hunting season targeting the local breeding population, declines in adult survival documented during this study are not reducing the population. Alternative management strategies may be necessary to reduce the population to achieve the management objective.